easy-errors

easy-errors

This packages offeres often used tasks for validating given input for interfaces. You can validate input and expect mandatory attributes. You may also secure input by encoding it for HTML and avoid XSS attacks.

Installation

npm install easy-errors

Usage

Validation

When you provide data in form of an object for an interface (e.g. method, http interface, ...) you sometimes rely on attributes that have to be present. There is a validation method, which does exactly that.

const { validation } = require('easy-errors');

try {
  // call validation method. First parameter is the data, which should be tested. Second parameter is a 
  // list of attributes, which must be set in the data object (i.e. first parameter). If validation succeeds
  // the promise resolves without a value. If not it rejects with a MissingParametersError.
  
  await validation({ key: 10 }, ['key', 'test']);
  
  // [...] 
} catch(error) {
  console.error(error);
  # -> MissingAttributesError: 'test' is missing
}

Errors

When propagating errors you often want some meta data attached to it (e.g. code, message, ...). Maintaining this is cumbersome and should be done descriptively. This package introduces common errors with useful meta information attached to it that you can use. Also the validation method uses them as well!

const { errors } = require('easy-errors');
throw new errors.MissingParametersError();

You can be provide an object with more meta data, which will be added to the error.

const { errors } = require('easy-errors');
throw new errors.MissingParametersError({ detail: ['There is something wrong'], success: false });

See a full list of the introduced errors:

Name	Message	Code	Status Code
MissingParametersError	Some parameters are missing	10000	400
InvalidParametersError	Some parameters are invalid	10001	400
NotFoundError	The requested resources was not found	10002	404
ForbiddenError	You are not allowed to perform this action	10003	403
UnauthorizedError	There was an error with the authorization	10004	401
ConfigurationError	There was an configuration error	10005	500
TopicNotFoundError	The requested topic is not available or was not found	10006	404
SubscriptionError	The device could not be subscribed to the topic	10007	500
EndpointNotFoundError	The requested endpoint is not available or was not found	10008	404
ConflictError	The request could not be completed due to a conflict with the current state of the target resource	10009	409
DecodingError	Signature mismatch	10010	401
TokenExpirationError	JWT Token lifetime has expired	10011	401

The Status Code is a value, which is a recommendation as a response status, when dealing with HTTP/S. The Code is something to identify the error by.

Secure

You can encode input for HTML and thus avoid XSS attacks.

const { secure } = require('easy-errors');
const xssAttack = '<script>alert("DANGER")</script>'

secure.encodeString(xssAttack); // -> &lt;script>alert("DANGER")&lt;/script>

License

Copyright 2019 appcom interactive GmbH Copyright 2019 NanoGiants GmbH

Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.